sailboats can injure and kill

[Rakuflames]

Originally Posted by zeehag

i enjoyed sailing in and near tampa bay, and rest of west florida --we sailed like wind in the tboomers they have daily there--for a year..was fun. scary but great weather experience. the storms come up at certain time every day and dissipate rapidly. to avoid these , just sail 40 miles off coast.
the funnest weather to learn anywhere is the localized weather patterns--is different everywhere and all places have quirks and traps. is fun to learn how to spot them before they get to you. challenging and fun.

You must have been a little north of where I am (ten miles can make all the difference).

Personally I find sailing on Tampa Bay boring, but the west coast of Florida is great because there are a lot of interesting places to go. Being single, I'm not guaranteed a sailing companion for a longer trip, but you can hopscotch down the coast, and the places to pull in are actually both interesting and beautiful.

The storms you're talking about are predictable, but you can't avoid all big thunderstorms by staying off the coast. The coast itself is often clear of storms; the afternoon storms around Tampa Bay typically form and stay inland.

I keep mentioning the one we had a year ago April. Storms were predicted for that day but no one expected 80 mph winds. In "my" section of Boca Ciega Bay, 8 boats went aground, but none of them were on moorings. The storm my neighbor got caught in stayed offshore, and that storm was not connected with a larger weather system -- a true "pop-up."

We don't have daily t-boomers where I am, in the southern part of the Pinellas peninsula, and yet ten miles north of here, some summers they get pounded every day.

[Rakuflames]

Originally Posted by DeepFrz

Just to clarify things here. Derechos are not microbursts.

No, but they generate microbursts. Often the damage is mistaken as tornado damage until evaluated by meteorologists.

[zeehag]

we sailed 6000 miles up and down fla in th ebay and out the bay , fort jefferson to slidell louisiana for a near year--11 months. was a goood trip--we were into tampa bay for provisions, anchored in vinoy basin on windless days and inmanatee river on windy ones, spent glorious time in regatta pointe and got some wonderful pix from this trip. we also sailed some intense --labelled by noaa as severe--tboomers, and spent some nights enjoying confused seas and high winds and lightning ---and we enjoyed some lovely nights with full moon and stars and moderate breezes.but the storms do not get too far from shore. we avoided them when we sailed 40 miles off. we hit them when we sailed within 30 miles of shore. florida has daily tboomers in summers. especially in june and july. only months we didnt sail there was jan and feb.

flame--re read the article posted by minaret. you missed something.http://www.spc.noaa.gov/misc/AbtDere....htm#tornadoes

[Rakuflames]

Originally Posted by carstenb

If i recall my meteorology courses from my yachtmaster time, katabtic winds are generated where high mountains fall steeply down to sea, eamples alps, the agean parts of norway.

I haven't been in tampa for a few years, has the army corps of engineers built a couple of mountains there?

has alpine climbing becaome a serious local sport?

Just asking raku - maybe you could post a pic or two of the mountains in tampa.

Course, i could be wrong"........

Since you didn't quote anytyhing, I am left scratching my head wondering why you think anyone thinks there are mountains anywhere in Florida. I never claimed that Florida has katabatic winds. Perhaps I left out a "not" or something. I'll never know. It would help if you quoted the posts you respond to, just sayin ...

[jackdale]

I learned to sail on Galveston Bay. I seem to remember many thunderstorms on the Friday night races.

[Sailor g]

Originally Posted by minaret

All regional names for winds dictated by local effects. Derecho is an old word for a particular rare meteorological effect, the term is Spanish. A Tornado is a swirling wind, a Derecho is a straight line wind in Spanish.

Just thought as long as we were scaring each other with tales of dangerous weather effects, I'd throw that in the mix. Look at the video of the Pakwash Derecho under photos and videos in the link I posted, the ground and air footage is absolutely terrifying...

Amazing photos, Minaret! I would love to save them for my class (I teach high school science). I think elefantes in Mexico are kadiabatic winds like the one that hit Newt.

Trying to remember my meteorology class (decades ago) but am confusing kadiabatic & adiabatic (is one wind & the other just temperature change from altitude?). Anyone know what I am talking about with that or am I totally off? I'm too tired to research tonight.
Didn't Mark Twain name the Washoe Zephyr (another kadiabatic wind?) so I think Newt has a right to name the one in the PNW (I mean besides the names he called it that night. The Newt has a ring to it.

[jackdale]

Originally Posted by Sailor g

Amazing photos, Minaret! I would love to save them for my class (I teach high school science). I think elefantes in Mexico are kadiabatic winds like the one that hit Newt.

Trying to remember my meteorology class (decades ago) but am confusing kadiabatic & adiabatic (is one wind & the other just temperature change from altitude?). Anyone know what I am talking about with that or am I totally off? I'm too tired to research tonight.
Didn't Mark Twain name the Washoe Zephyr (another kadiabatic wind?) so I think Newt has a right to name the one in the PNW (I mean besides the names he called it that night. The Newt has a ring to it.

Some research

Adiabatic heating also occurs in the Earth's atmosphere when an air mass descends, for example, in a katabatic wind or Foehn or chinook wind flowing downhill over a mountain range. When a parcel of air descends, the pressure on the parcel increases. Due to this increase in pressure, the parcel's volume decreases and its temperature increases, thus increasing the internal energy.

[Rakuflames]

Originally Posted by jackdale

I learned to sail on Galveston Bay. I seem to remember many thunderstorms on the Friday night races.

It reminds me of the Coast Guard's new rules in the wake of the tragedy off San Fransisco when a racing boat went too close to a rocky coast. We all "should" know that what we do is dangerous, and the racers I know are diehards who aren't going to back away easily. It seems to me that putting out buoys to keep boats a safe distance from the rocks would be a simple solution. Then the racers would simply have to choose their tactics within those restrictions.

The races here carry on no matter what the weather. Two of the last three "Good Old Boat" races have taken place in strong winds -- gusts of 45 mph. I think it was last year a boat with a crew of six sank in the rough water and winds -- Tampa Bay is shallow and Zeehag wasn't exaggerating when she talked about "confused waters." Fortunately the skipper was really smart and went off the boat with a big piece of line. He tied all six crew members together, which greatly aided the rescuers.

The year before an experienced crew made two mistakes that sank the boat -- first a bad tack, where the spinnaker scooped up a lot of water, pulling the bow down -- and then, wouldn't you know they hadn't closed the forward hatch after passing the spinnaker up, so the boat rapidly filled with water. Like most of Tampa Bay, shallow enough that part of the mast was above the water line, but visibility was still poor because of the weather conditions, so it was a real navigation hazard for the rest of the race.

Stuff happens, and I'm glad Newt is healing, but it's colossally inconvenient to have a banged up arm.

[Rakuflames]

Originally Posted by zeehag

we sailed 6000 miles up and down fla in th ebay and out the bay , fort jefferson to slidell louisiana for a near year--11 months. was a goood trip--we were into tampa bay for provisions, anchored in vinoy basin on windless days and inmanatee river on windy ones, spent glorious time in regatta pointe and got some wonderful pix from this trip. we also sailed some intense --labelled by noaa as severe--tboomers, and spent some nights enjoying confused seas and high winds and lightning ---and we enjoyed some lovely nights with full moon and stars and moderate breezes.but the storms do not get too far from shore. we avoided them when we sailed 40 miles off. we hit them when we sailed within 30 miles of shore. florida has daily tboomers in summers. especially in june and july. only months we didnt sail there was jan and feb.

flame--re read the article posted by minaret. you missed something.Facts About Derechos - Very Damaging Windstorms

Not sure what you think I missed. I'm pretty familiar with weather systems that form tornadoes, and bow echoes. The "derecho" term is new to me, but new to others here also. Maybe I stated something less than perfectly clearly.

Somewhere my response to this disappeared. I included a picture of radar of the Gulf of Mexico around 10PM last night. The weather was very active out in the middle of the Gulf. If you did all that sailing across the Gulf of Mexico and never got caught by a substantial thunderstorm you were pretty lucky. (The active storm season has been considerably longer than usual this year; it's unseasonably warm here right now.)

Storms that form over land don't go way out in the Gulf. Different storms form in the Gulf, and they can be real honkers.

[s/v Beth]

Alright, all you armchair sailors out there that really want to get in on this.
I was at 48 deg 9 minutes N and about 123 degrees 38 min west with a 20 knot wind from the NW coming down the strait. It had been continuous and constant all night. I thought I would duck into the Freshwater Bay area just east of Striped Peak and take advantage of the current going against the tide in the bay. (kinda of a back eddy at that time). I was hit with a 30 knot wind from the SW and that is when the stuff hit the fan. That is according to my recollection. Once I can get back to my boat I can give you a blow by blow description (if my GPS has not been erased).
Having learned most of my big boat handling around the Carribbean I must say nobody had lectured me on these type of winds. Going to be much more careful close to the shore from now on.

[Rakuflames]

Originally Posted by s/v Beth

Alright, all you armchair sailors out there that really want to get in on this.
I was at 48 deg 9 minutes N and about 123 degrees 38 min west with a 20 knot wind from the NW coming down the strait. It had been continuous and constant all night. I thought I would duck into the Freshwater Bay area just east of Striped Peak and take advantage of the current going against the tide in the bay. (kinda of a back eddy at that time). I was hit with a 30 knot wind from the SW and that is when the stuff hit the fan. That is according to my recollection. Once I can get back to my boat I can give you a blow by blow description (if my GPS has not been erased).
Having learned most of my big boat handling around the Carribbean I must say nobody had lectured me on these type of winds. Going to be much more careful close to the shore from now on.

Maybe we should call it a "Newt Shift?"

[jackdale]

Owen Lange has written several books on local weather hazards in the area. He makes no references to issues in this particular area.

One possibility:

The NW wind in Juan de Fuca in the summer daytime is often an anabatic (onshore) wind. As the temperature drops you can get a offshore breeze developing. If there was a a systemic SW wind associated with a low pressure the two of them could result in a strong SW wind.

A katabatic wind off the Olympic mountains is also possibility, but Lange makes no reference that in his books.

[Dockhead]

Originally Posted by minaret

They don't FORM at sea. They can, however, move out to sea, just as a hurricane can move ashore. Examples-

June 2012 North American derecho - Wikipedia, the free encyclopedia


The damaging winds continued eastward across the Chesapeake Bay towards the Atlantic Ocean, losing little strength despite the cooler marine layer.[11] The derecho emerged into the Atlantic Ocean shortly before 2:00 a.m. EDT (0600 UTC) on June 30, while still producing winds as high as 81 mph (130 km/h) at the coast in Tuckerton, New Jersey and strong and damaging winds on the Delmarva Peninsula.[6] Numerous special marine warnings were issued for the coastal waters of affected states by the NWS as the derecho moved out to sea.[12] The storm dissipated around 4:00 a.m. over the Atlantic south of Long Island, New York


Dan and Jaye's cruising blog: Kumatage (reflections on the water): Derecho!


Violent storm that slammed South Jersey is known as derecho | NJ.com

True of course!

[Dockhead]

Originally Posted by s/v Beth

Alright, all you armchair sailors out there that really want to get in on this.
I was at 48 deg 9 minutes N and about 123 degrees 38 min west with a 20 knot wind from the NW coming down the strait. It had been continuous and constant all night. I thought I would duck into the Freshwater Bay area just east of Striped Peak and take advantage of the current going against the tide in the bay. (kinda of a back eddy at that time). I was hit with a 30 knot wind from the SW and that is when the stuff hit the fan. That is according to my recollection. Once I can get back to my boat I can give you a blow by blow description (if my GPS has not been erased).
Having learned most of my big boat handling around the Carribbean I must say nobody had lectured me on these type of winds. Going to be much more careful close to the shore from now on.

We've all had that lesson sooner or later -- it is very sad that yours was so painful!

Sounds to me like a katabatic wind, which forms pretty commonly where you have high terrain next to the ocean. I'm sure you know the mechanism -- air mass cools off at higher altitudes and eventually becomes heavier than the warm air at sea level -- at some point it falls to sea level in a kind of avalanche, rolling down the slope of the mountains.

Katabatic winds can be localized or not. The Bora is a big katabatic wind -- got whacked by that once in the Adriatic, in Croatia. Localized ones can ruin your day, too.

But any kind of high terrain next to the shore can cause unpleasant wind effects of different kinds and not just katabatic winds. Wind gets funneled between high islands, so a 20 knot wind can be magnified up to 40 -- seen that in the Aegean a few times. It can be dangerous not just because of the magnification of wind force, but because the wind direction can be changed as well, as the wind is bent around the high terrain.

Your conclusion is right -- be careful around the shore, where there is any kind of terrain!

[Dockhead]

Originally Posted by jackdale

I learned to sail on Galveston Bay. I seem to remember many thunderstorms on the Friday night races.

Ha, so did I! More decades ago than I like to think about. Racing 420's, those nasty little unstable overpowered racing dinghies. That was before Goretex, so the constant T-storms were really unpleasant. Good thing it's so warm there.